Hide regs_invalidated_by_call etc.

Hide regs_invalidated_by_call etc.

The previous patches removed all target-independent uses of
regs_invalidated_by_call, call_used_or_fixed_regs and
call_used_or_fixed_reg_p.  This patch therefore restricts
them to target-specific code (and reginfo.c, which sets them up).

2019-09-30  Richard Sandiford  <richard.sandiford@arm.com>

gcc/
	* hard-reg-set.h (regs_invalidated_by_call): Only define if
	IN_TARGET_CODE.
	(call_used_or_fixed_regs): Likewise.
	(call_used_or_fixed_reg_p): Likewise.
	* reginfo.c (regs_invalidated_by_call): New macro.

From-SVN: r276338